substitute of it), as it simulcasts BBC Two outside of its main broadcast hours. BBC Choice also briefly had regional variations for these areas. ITV was originally established as a network of some 14 separate companies, each designated a region of coverage (see History of ITV). Each company provided a mixture of local programming for its own coverage area, as well as airing nationwide networked programmes (usually produced by one of the contractors). ITV has traditionally included more regional variations than the BBC, though since consolidation and majority ownership by ITV plc regional variations on the network are far fewer which in England consists only of regional news and a monthly political discussion programme, and often are no more than the minimum requirements as set by Ofcom. Channel 4 and Channel 5 provide no regional variations for programming or continuity, but do sell localized advertising. A notable exception was S4C, a channel in Wales which broadcast in place of Channel 4, and primarily broadcast Welsh-language programming of interest to the local audience, as well as programming acquired from Channel 4 (but not always in pattern). Although S4C was a de facto regional variation of Channel 4, it was a separate channel in its own right. During the transition to digital television, Channel 4 became available over-the-air in Wales on Freeview alongside S4C, which subsequently provided an alternate feed that only carried Welsh programming. Sky News and Sky1 also provide a variant of their stations for the Republic of Ireland, although specific Sky News coverage for the Republic of Ireland is extremely limited, due in part to the channel with Irish content closing on 3 November 2006, and Sky1's variant is purely an advertising opt-out. United States U.S. broadcast television is heavily regionalised to an extent due to the business model of its major commercial networks, which enter into agreements with stations in each media market to carry their national programming, similarly to a franchise. As the FCC enforces a limit on the market share of broadcasters, networks typically have owned and operated (O&O) stations only in major and key markets, and rely on affiliates to reach the remainder of the country. Outside of network programming (which usually consists of two or more hours of prime time programmes per-night at a minimum, and may also include national news, sports and daytime programmes), the scheduling of each station's programming varies, and usually